Variable speed driving or transmitting gear



Aug 9, 1932g s. HARBER ET AL 1,871,320

VARIABLE SPEED DRIVING 0R TRANSMITTING GEAR INVENTORS LAURENCE SEYMUR BARBER ANB JOHNED Anp POINTUN ATTORNEY Aug. 9, 1932. L.. s. HARBER ET AL v f 1,871,320

VARIABLE SPEED DRIVING OR TRANSMITTING GEAR Filed July 25, 1928 4'Sheets-Sheeb 2 INVENTORS LA URENOE SEYMOUR HARPER AND JOHN E WARD POINTQN Aug- 9, 1932- L. s. HARBER ET A1. 1,871,320

VARIABLE SPEED DRIVING OR TRANSMITTING GEAR Filed July 23, 1928 4 sheets-sheet; 3

0 r 1f Y 31 14' 1 E P 'l2-:9 1 @D C5 E t L 1 S j1.2 E l 27 IN VEN TORS LAURENCE SEYMOUR HARBER AND JOHN .E'DW RD .POINQTON A T TORNEY ug- 9, 1932- L.. s. HARBER ET AL 1,871,320

VARIABLE SPEED DRIVING OR TRANSMITTING GEAR Filed July 23, 1928 4 Sheets-Sheet 4 IN VEN TORS LAURENCE' SEYMOUR hVA'RBEH ANB -JOHN EBWARD POINTON -ATTQRNEY Patented Aug. 9, 1932 imitan STATES ement 'ortica L-AURENCE SEYMOUR HARBER AND JOHN EDVV'ARD` POINTONQOF PETERBOROUGH, ENGLAND, .ASSIGNORS TO BAKER PERKINS COMPANY, INCORPORATED, NEW

YORK, N. Y.

VARIABLE SPE-ED DRIVING B. TRANSMITTING GEAR Application ile-d J'111y123, 1928, Serial No. 294,782, and inr Great Britain August 9,1927'.V

rl'his invention relates to variable speed The object of the invention is to provideV for'theready setting of machines for operating at the required speeds and for the required periods to give a desired result, as for example, the production of a homogeneous mixture at aI consistency suited for a given purpose. A

The invent-ion comprises Athe combination with variable speed driving or power transmitting elements, of means providing for the ready setting or adjustment of such mechanism to enable a machineto be run for a given period with a varying range of ratios between. the driving and driven parts of said elements, followed if desired by a period of running at a xed rat-io, and the automatic stoppage of the machine at the conclusion of the required full period of running or operation.

Referring to the four accompanying sheets of explanatory drawings Figure l is an elevation representing suffi? cient of a dough mixing or like machine to illustrate the application of the invention thereto. 1'

Figures Zand 8 are end views (takenrfromopposite ends of the machine). Y p

Figure 4 is a sectional elevation and Figure 5 is a plan showing a portion of the mechanism hereinafter referred to.

Figure 6 is a sectional elevation and Figure 7 a sectional plan showing, to a larger scale, details ,of Vthe starting. handle and timing mechanism associated therewith.

Like referenceletters in the diferentviews indicate like parts. f

' In one convenientapplication of the invention to a mixing or like machine as illustrated by the drawings, comprising a beater,

whisk or its equivalent (indicated at Figure 1 by the centre line a) adapted to be rotated and otherwise moved in a pan or receptacle b containing the materials, the driving power,

' `preferably obtained through an electric motor c, istransmitted through` gearing and a.pair of adjust-able cone pulleys cl and e, (each pulleybeing made up of a pair of discs havingtheir adjacent faces coned), of which l forms the driving and e the driven pulley of the combination. The transmission from one pulley to t-he other is effected by any suitable belt or like connection as indicated at 7" Figure 4.

The simultaneous adjustment of the effective diameters, or the belt engaging diameters of the said cone pulleys al and e (theone being` increased and the other decreased) ,1s obtained as follows: i'

, One end of the shaft g carrying the driving pulley Z is connected through a worm reduction gear with aV layshaft or spindle z' which is also connected through another worm reduction gear j with a stem or rod la havingrigxht and left hand screw threads thereon. spring clutch Z yis interposed between the worm wheel of the last named reduction gear y' andthe said screwed rod 7c, permitting of al movement of the worm wheel relatively to the rod when required, as hereinafter described. The right and left hand Y threads of the stem or. rod'k engage nuts as m and n forming part of or. connected with arms or yframes 0 and p whichare pivoted at g, r on a crosssupport s so that on the rota,-

tion of the rod lo they receive a rocking mo-l tion which varies the distance between the discs forming the coned pulleys d and e aforesaid, causing the one pair of discs to approach and the other pair to recede from each other and thus altering the speed ratio between the driving pulley and the driveny pulley e.

The said rocking arms or frames 0 and p are set to give the required kstarting speed ratio by the operation of a hand wheelt fixed at one end of the rod or stem 7c. appropriately graduated dial u is geared or arranged in operative connection with'the rod 7c to facilitate such setting. Such a dial is shown at u, Figures 1 and 5. The rotation of the dial is automatically effected on the `rotation of rod 7c with which`the dial is 1 connectedV through Yworm` gear train; u V(Figure 5). A iixed index is placed above Anl the dial as at w, Figure l. Stops as m and y on the rod la limit the movement of the arms 0 and p in each direction, the stop y being adjustable by a sliding movement in a slot in the machine framing and fitted-with a clamping Anut z.

The automatic reduction or variation of the speed ratio between the driving and driven pulleys .CZ and e begins wfiththe starting of the machine, due to themovement imparted to the rocking arms o and pby the rotation of the screwed Vrod 7c through the gears 7L and aforesaid. -Such variation continuously. progresses Auntil the movement Y of the rocking arms'is arrested by the adjustable stop or abutment y.V The transmission between the drivi-nganddriven pulleys can then` continue, .without further variation of the speed ratio betweenthem, until lthev desired complete period of operation of' the machine on thegmaterialsunder treatment has been completed.. Because of the-aforesaid spring clutchY connection. Z, interposed e between the screwed stem or rod c and the worm wheel m ofthe ygear.jtlirougll'-which it receives its Y Vratio between the driving anddriven coneV rotary motion, no such motion V.will lbe imparted tothe screwed rod duringv the run-ning ofthe machinethrough the periodlfof a fixed wf pulleys asthe. `clutch will automatically slip (fetiw or release when turthermevement ofthe rockingarms is prevented bythe adjustable abutment yaforesaid. f f

.The machineisset'to give `the required full periodnt operation or'. treatment otra given ,.massqof .materials inthe pan or re-` ceptacle .as .fellows :The electric motor. cisstartedby means of a'handle 1 Yoperating a exible wire 2 and so` pulling the. startingswitch lever 3 to the onf position. Thersaid switch lever is indicated by .dotted lines inFi'gureV 1 with an'l end .of the'flexible wire 2 attached to it and alsoaspring- .hereinafterreferred to. v On :the starting handle shaft .5 is; loosely mounted the drum or disc 6 on. which one end 'of the Y flexiblewire 2 is coiled, and such disc has a aforesaid .lay shaft fthrough which thefscrewed rod c is rotated. The gear between the said wormwheel 12 and-lay shaft z' com `prises-worms 13 andlli andwormwheel 15. e

rlfhe first named clutch memberl() has a suitably' graduated settingor `timing'dial or knobel arranged therewith such that the said projecting pin orpeg .9 maybe set at the l necessary position toefect the release of the trigger 8 at the required time after starting the machine and thus automaticallystop the motor c. Y

After the automatic stopping of the motorv by the means aforesaid, the-latter are automatically re-set at the starting position on the turning of the handle 1 :torre-starting the motor c. For such re-setting a gear wheel 177on' the lhandle shaft or spindle 5 engages teeth 18 on the clutch memberl() carrying the trigger releasingpeg. v9.- -From the saidlgear wheel 17there projects peg 19 which is in abutment with the adjustable Vstop 20 when the electric, mo'tQrisstarted.

YThe 'dog'piece or projection 21'from the handle;A shaft abuts `aga-instfthe aforesaid pro-V jection 7 from the wirecoiling disc or drum 6, the saidpart21 alsoabuts against they said peg y19* from they wheel 17 VAti-Figures and 7 the parts are shown in the positions taken up when the motor rhas been just started or re-started. During thek running of the motor the-peg 19' and the dog 21 will move away in the direction of the arrow 22 from thepositions shown atfFig-ures 6 at' the same rate that' the peg 9. approaches the trigger 8. When, afterthe tripping of the trigger` by thev peg V9 as aforesaidA for stoppin-g thermo- Y tor, the latter is re-started by a movementof Y thehandlel the` direction ofthe arrow 23 (Figure 6) the dog or projection 21 of the handle shaft in moving the winding disc Y or drum v6.- will also move back` the peg 19 to the-.adjustable yabutment20 and in so doing will automatically'reset the mechanism to the lstarting position.

v For an emergencystoppage of themotor (independently of the automatic stop afore' said) the trigger 8 may be released by hand through cam 24 (Figures 6 and 7) operated by handle25 (Figure 5) with the consequent stopping of the motor l(by the laction-.of springe Figurel) at any moment. during the run ofthe machine.

.-A mixing machine having this invention applied thereto may be readily set tQ-meetvarying conditions. Thus, forexample,l for a full run or period ofroperation extending` over say twenty minutes, the machine,V maybe set toV start with a beaterspeedlat the-rate of say twelve revolutions per. min-utefgradually slowing down. insay. three minutes-to af rate of eight-revolutions per minute andcontin-V ning. uniformly at they latter rate-throughout the remaining seventeen minutesoi:I the run. Otherspeeds and times maybe obtained: by

the mere setting of the change Vdial u. 1 movement ofthe hand wheel t of the screwed.

rod la', andthe adjustablev .abutment y, and

the timing dial 16 as,aforesaid,itothe desired figures ory graduations of such parts.

The automatic progressive reduction. of thespeed ratio between tlietlriving anddriven.

pulleys d. and ev by the movement imparted as.

aforesaid to the rocking armsoand p, may be prevented if desired by disconnecting the clutch Z on the screwed rod lo by means of the hand operated lever 26. The beater or operative element a of the machine can then be rotated at a uniform speed if so required throughout the period between the starting and stopping of the machine.

The transmission between the shaft 27 (carrying the driven pulley e) and the operative element a of the machine may be effected through any ordinary gear, as for example,

the wheels 28, 29, 30, 31, 32 and 33.

The mechanism employed in the application of the invention may be modified in various ways to meet varying services or requirements.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

l. In combination with a machine having a driving motor and a switch in circuit therewith, a starting handle shaft, a winding drum freely rotatable on said shaft, a cable connecting said drum and switch, a spring associated with said switch to hold it normally open, a rotatable indicator member, a friction clutch member integral therewith, a lay spindle operatively connected to said motor, a second clutch member arranged to cooperate with the first-mentioned clutch member and having a wheel geared to said lay spindle, a releasing peg mounted on said firstmentioned member of the friction clutch, a spring-controlled trigger situated in the path of movement of said peg, said trigger arranged for releasable engagement with said cable winding drum, a resetting dog and a resetting gear fixed to the starting handle shaft, a stop carried by said resetting gear,

an adjustable abutment mounted on a fixed support and projecting into the path of said peg stop, and to a co-acting gear integral with the first-mentioned clutch member, for the purposes set forth.

2. The combination of a machine, a driving motor therefor, a lay spindle operatively connected to said motor, a switch controlling a power circuit to said motor, a rotatable drum, a cable operatively connecting said drum and switch for closing the switch, a spring connected to said switch for holding it normally open, a starting handle and a dog operated thereby to rotate lthe drum and wind the cable, a trigger releasably holding the drum, a trigger releasing peg, means including a friction clutch driven by said lay shaft for revolving the peg to displace the trigger, and resetting devices actuated by said handle, independently of the operation of the layV shaft, for restoring said peg to its initial position.

In testimony whereof we have signed our names to this specification.

LAURENCE SEYMOUR HARBER.

'e5A JOHN EDWARD PorNroN. 

